Table of contents macro is not always generated as standalone macro

It seems that some source content like this:

<p><u><strong>Table of Contents :</strong></u></p><p><u><strong><ac:macro ac:name="toc" /><br /></strong></u></p>

is imported in XWiki like this:

__**Table of Contents :**__

__**{{toc/}}
**__

The table of contents is thus inline (in the formatting) and displaying on the screen an error:

"The [toc] macro is a standalone macro and it cannot be used inline"

We should make sure that the toc macro is generated block (stanlone) no matter what.